// spinlock.h
// A simple multiprocessor safe spinlock

/*
   Copyright 2006 Corey Tabaka

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

#ifndef __SPINLOCK_H__
#define __SPINLOCK_H__

#ifdef __cplusplus
extern "C" {
#endif

typedef volatile int spinlock_t;

#define SPINLOCK_UNLOCKED 0
#define SPINLOCK_LOCKED 1

void spinlock_init(spinlock_t*);
int spinlock_wait(spinlock_t*);
void spinlock_signal(spinlock_t*);
int spinlock_try(spinlock_t*);

#ifdef __cplusplus
}
#endif

#endif
